Siphon



A. J. GURCK Jan. 22, 1935.

SIPHON Filed Sept. 9, 1935 patented Jan. 22, 193K UNITED STATES H slrnon Arnoldus-Johannes Gurck, The Hague,

Netherlands Application September 9, 1933,.Serial No. 688,845 In the Netherlands September-27, 1932 It'is well-known in the art that both in bell siphons and in fixed siphons the descending shank must be narrowed, in order that the air may be rapidly expelled from the siphon.

The object of the present invention'is a siphon adapted to be operated by water injection and which can be caused to start suction very rapidly, for'example,' bypressinga button, so as to readily discharge the normal volume of water from a lavatory flushing cistern.

According to the present invention, the taper which is usually provided for in the descending shank of the siphon, is provided wholly or in part in the siphon bend. Preferably the whole nozzleshaped portion, which forms the transition from the normal cross section of the suction shank to the narrowest part of the descending shank, is contained between the highest point and the end of the bend on the side of the descending shank.

The cross section of the siphon at the highest point of the bend is preferably more or less flattened, i. e. the length of its horizontal axis exceeds that of the perpendicular or radial axis. The reason for this is that, when the siphonbegins to act, the air in the bend can be expelled more quickly if the latter is flattened as described above. A comparatively sharp taper, so that the minimum cross sectional area is at the end of the bend, facilitates the rapid expulsion of the air, and owing thereto the suction of the siphon can be started with the minimum quantity of water and consequently with very little power consumption.

The water level in the suction shank is raised by the injection of water in indirect ratio with the cross sectional area of the space through which it has to travel. It is therefore advantageous to design the suction shank narrower than the drop pipe which forms the continuation of the descending siphon shank, apart from the fact that the lower end of the suction shank may be flared to prevent any contraction of the water flow.

The drawing shows, by way of example only,

an embodiment of the present invention. Fig. 1

is a vertical section through the siphon, while Figs. 2a, 2b2g are cross sections on the lines shown in Fig. 1 by Ila, IIbIIg.

The siphon is shown to be mounted in the usual way in a lavatory flushing box of which only part of the bottom 1 is illustrated. A drop pipe leading to the lavatory is connected at 2 with the descending shank of the siphon, while the pipe which connects the ordinary injection nozzle 4 with a press button or the like is joined at 3.

' ,3 Claims. (Crier-20) The suction shank 5 of the siphon has at'its lower end a circular cross section, the area of which is smaller than that of the cross section 'offthe drop pipe, and is also smaller than the cross sectional area at the lower end of the descending siphon shank 6. Therefore, the area of the'crosssection IIg exceeds that of the cross section IIa. Both cross sections are circular.

In the upper portion of the suction shank 5, the circular cross section 11:; gradually changes into the oval cross section IIc (see also Fig. 2b), but the cross sectional area remains substantially the same. Also in the first half of the bend the cross sectional area remains practically constant, i. e. Fig. 2d is practically congruent with Fig. 2c. The second half of the bend, however, i. e. the portion between the cross section 'IId and the cross section II is tapered'so as to form a nozzle. The cross section III (see Fig. 2]) is circular, but its area is considerably smaller than that of the circular cross section shown in Fig. 2a, or than the oval cross section shown in Fig. 2d. The length of the horizontal axis of the ellipse shown in Fig. 2d (compare also Fig. 2e) gradually decreases, until it is equal to that of the perpendicular axis in Fig. 2d.

The volume of the water which is lifted from the level 7 is practically proportional to the kinetic energy of the jet of water which issues from the nozzle 4. If, therefore, the suction shank 5 has the smallest admissible cross section, the height of the rise is maximum. The required height of the rise as well as the volume of the siphon between the level '7 in the suction shank and the cross section II), are reduced to a minimum in consequence of the oval form of the cross section IIkZ at the highest point of the bend. Consequently, the energy exercised by the press button need only be very small.

In addition to this, the bending round of the water column in the flattened bend causes less loss and irregularity in the stream than in a bend having circular cross sections. Such a bend also permits the air to be expelled more rapidly, particularly if the second half of the bend is tapered. In the second half of the bend, between 1111 and II the water should be accelerated before it falls by gravity. It is for this reason that the whole nozzle-like taper, which is so important for the ready functioning of the siphon, has been concentrated in the bend. Also this measure contributes towards the reduction of the energy required for starting the siphonic'action.

Finally, the new type of siphon causes only very small losses in flow, with the result that the water is discharged in a very short time.

It is obvious that the smallest cross section (11 may also be placed a little farther down than is shown in the drawing, and also that the nozzle-shaped taper need not necessarily begin at the highest point of the bend. However, the higher the smallest. cross section II is located, the more gradually can the diameter of the diffuser-like shank 6 be increased, which means that the water column will remain all the more compact and the air will be better expelled when" the siphon begins to function.

What I claim is:-

1. An inverted U-shaped siphon tube comprising a suction shank and a descending shank connected at their upper endsby aben'd ovalincross section, each of said shanks being circular at-its lower end with the lower end of the descending shank of greater cross area than the lower end of the suction shank, and said shanks gradually merging at their upper ends-into the oval. for-mation of the connecting bend.

2. An inverted. U-shaped siphon tube comprising asuctionshank and adescending shank connected at their upper ends by abend oval in cross section, each. of said shanks being circular at its lower endwith the lower end of the descending shank of greater cr'oss area than the lower end of the suction shank; said descending shank gradually tapering toward its upper end and merging into the oval formation of the corresponding end of the bend, the merging part of the bend with the descending shank being of less cross area than the cross area of the intermediate part of the bend toform a nozzle. at the upper part of the descending shank;. and said suction shank'gradually merging into the oval formation at the corresponding end of the bend, the

merging part of the bend with the suction shank having approximately the same cross area as the intermediate/part of the bend.

3; An inverted U-shaped siphon tube comprising suction and descending shanks connected at their upper ends by a bend tapering from its intermediate part to the end communicating with the descending shank, said descending shank having at its lower part a greater cross area than that-of theilower partof the suction shank, and said. descending shank gradually tapering towarditsupper endlto merge into the communicating end of the bend, with thetapering end part of the bend forming a restricted nozzle to discharge from the bend into the descending shanln.

ARNOLDUSJOI-IANNES GURCK. 

